Artificial limb



O. LE G. DILWORTH.

ARTIFICIAL LIMB. APPLICATION FILED IuLY 22. 1919.

0. LE G. DILWORTH.

ARTIFICIAL LINIB. APPLICATION FILED IuLY 22, 1919.

Patented July 26, 1921.

2 SHEETS-SHEET 2 7X INVENTOR UNITED STATES PATENT OFFICE.

OTTO LE GRAND DILWORTH, or HARTFORD, CONNECTICUT.

ARTIFICIAL LIMB.

Application led July 22,

T all 'wiz-om t may concern Be it known that l, OTTO LE GRAND DIL- won'ri-r. a citizen of the United States and a resident of Hartford, in the county of Hartford and State of Connecticut, have invented a new and improved Artificial Limb, of which the following is a specification.

An object of. the invention, among others, is to provide an artificial hand that may be readily operated and the movements of which shall closely imitatevthose of natural members.

One form of device embodying my invention and in the construction and use of which the Objects herein set out, as well as Others, may be attained, is illustrated in the accompanying drawings, in which- Figure 1 is a view of my improved hand and arm with parts broken` away to show construction, the forearm being bent up-. wardly.

`Fig. 2 is a similar view but looking toward the baclr of the hand.

Fig. 3 is a detail view illustrating mechanism for moving the thumb.

Fig. l is a view of a fragment of the thumb illustrating' the construction thereof.

F 5 is detail view, scale enlarged, of the finger operating mechanism with parts broken away to show construction.

Fig. 6 is a detail view on plane denoted by dotted line 6 6 of F ig. 5.

F ig. 'T is a detail plan view of the supporting bar for the finger actuating mechamsm.

F 8 is a detail view illustrating a portion of the finger operating mechanism and the means for retaining the parts in unlocked condition.

F ig. 9 is a detail view in section through the cover of the h and and illustrating the mechanism for retaining the parts in unlocked condition.

in the accompanying drawings the numeral 10 indicates the upper arm and 11 the forearm of my improved device, the former being hollow, thus providing a recess to receive. the stump of the natural arm. The fore and upper arms may be constructed of any suitable, light material, common to structures of this class and the forearm is preferably hollow from end to end, and it is cut away on one side as at 12. The lower' end of the upper` arm 10 projects into the end of the forearm and these two members are pivotally united as by a pivot 13 secured Specicaton of Letters Patent.

Patented July 26'-, 1921. 1919. Serial No. 312,571.

in the member l0 with its ends projecting beyond the .sides of said member and enteringsupporting straps ll-l5 secured to Opposite sides of the forearm and projecting beyond its upper end, said straps having a swinging movement on said pivot.

The hand may be attached to the arm as by means of a` wrist piece 16 pivotally secured to the arm in any desired manner, the hand being pivotally secured to the wrist piece as may be desired. A thumb is movably attached to the hand in the usual position, the structure herein shown comprising a base L17-having a shank 18, said base fitting within a socket 19 at one edge of the hand, and as shown in F ig. 3 ofthe drawings. The base member is rotatably held in place as by means of a hollow nut 20 tting the screw threaded end of the Shank 18. An ear 22 extends from the center of the base, the outer end of this ear being formed on the arc of a circle. An inner thumb member 23, substantially round in cross section, has its inner end oppositely formed to correspond to the base above described,lthat is, said thumb member yhas a groove formed by ears 24; to receive the ear 22. The outer end of the inner thumb member is formed to substantially the shape of the inner end thereof, and a tip member 25 of thethumb has its inner end oppositely formed tothe thumb member 23, that is, with a cavity, the bottom of which is formed on the arc of a circle to receive the ears at the outer end of the inner thumb member, an ear 26 from the tip member fitting the groove in the outer end of the member 23. A spring 27, located in a recess between the inner and tip thumb members, forces the latter back to its open position. The thumb may be turned on the axis of the base as by means of the other hand, and it has a lug 28 projecting from an overhanging part 29 on the lower edge of the thumb member 23 that Overlies the edge of the socket 19, said lug being adapted, when the thumb is in one rotatable position, to enter a notch 30 in the edge of said socket and permit the member 23 to bend toward the hand. A thumb actuating cord 80 is secured to the front side of the tip- 25, said cord extending through a hole in the thumb member and base and through a passage 8l into a chamber 82 within the hand. Said cord will yield suiiiciently to permit the lug 28 to be removed from the notch 30. This chamber preferably opens from the back of the hand and is closed by a cover 34 that may be secured in place in any desired manner.

Finger and thumb actuating mechanism is inclosed within the chamber 82, such mechanism, in the structure herein shown,

comprising side plates 84 secured to the side walls of the chamber 82 opposite one another, each of these plates being thickened between its ends and having a guide groove 85. Cover rests 86 project from one edge of each plate and notches 87-88 are formed in the opposite edges of said plate, that is, in that edge of said plate toward the front of the hand. The plates are secured in place in any desired manner, as by screws proj ecting through the outer edges of the hand. A supporting bar 89 extends across the chamber, one end of the bar projecting into the'notch 88 and the opposite end into the notch 87, the bar at this end being of a width narrower than that of the notch so that the bar may have a slight lateral movement within said notch. A spring 132 having one end secured to a side plate and its other end engaged with the supporting bar holds it at one limit of its play as shown in Fig. 5 of the drawings.

A carrier plate 91 is pivotally supported at one end on the bar 89, preferably on a boss 92 thereon. This carrier plate has a groove extending lengthwise thereof to receive a retaining slide 93 that is movable in a direction lengthwise of the carrier plate. A hollow stud 94 is secured to the carrier plate 91 and projects through a slot in the retaining slide. A ratchet wheel is rotatably mounted on the stud 94, this ratchet having the usual peripheral teeth 95 and a set of holding teeth 96. The holding teeth are engaged by a carrier plate holding dog 97 pivotaliy mounted on the carrier plate and with its free end adapted to engage notches in the ends of the holding teeth, or in the spaces between the holding teeth. A retaining slide actuating spring 98 has one end in engagement with a screw stud 99 secured to the supporting bar, in the structure shown herein this stud passing through a filling plate 100 tightly secured within the groove in the carrier plate and through said plate. The other and active end of said spring thrusts against a carrier plate actuating stud 101 that is screw threaded into the dog 97 and projects on the opposite side thereof and loosely into an opening in the retaining slide 93, the slide and dog being thus connected and the spring engaging the dog with the holding` teeth of the ratchet and also moving the retaining slide in its groove in the carrier plate.

A carrier plate and pawl actuating lever 102 is pivotally mounted on the stud 99 and has a slot through which a screw pin 103,

secured to the carrier plate, extends. A finn ger actuating cord 90 has one end secured to said actuating lever, the opposite end being disposed of in a manner to be hereinafter set out. An actuating pawl 105 is pivotally mounted on the lever 102 with its teeth normally held in engagement with the ratchet teeth 95 as by means of a spring, one end of which is secured to the pawl and the other end of which is secured to the stud 94.

A retaining pawl 106 is pivotally secured to the carrier plate 91 on the opposite side thereof from the mechanism just hereinabove described, the end of said pawl being adapted to engagethe teeth of a retaining rack 133 secured to the supporting bar 89. A retaining pawl actuating pin 134 .projects from the pawl through a slot 109 in the carrier plate 91 and into a notch in the edge of the retaining slide 93, as shown in Fig. 5 of the drawings. The thumb actuating cord 80 is secured to the carrier plate, that, in its swinging movement, pulls upon or releases said cordand thus actuates the thumb member or permits it to be actuated.

A finger actuating rod 135 has its ends sliding in the guide grooves 85 in the side plates 84, this rod passing through knuckles 111 formed on a tie plate 112. This plate is secured to the stud 94 as by means of a headed screw 113. A screw 114 projects through the tie plate and serves as a fastening for one end of a link 115, the other end of said link being secured to the end of the hollow stud 94, as shown in Fig. 6 of the drawings. The link 115 has a sliding movement in a groove in a rocker 116 pivotally secured to a lateral projection from the supporting bar 89 and as by means of a pivot secured to said bar and extending into a hole 117 in the rocker (see dotted lines in Fig. 7 of the drawings). This connection between the carrier plate and the finger actuating mechanism and comprising the tie plate and the link prevents undue lateral play of the rod 135, and the location of one end of the supporting bar 89 in the notch 87 permits a slight movement of said bar sufficient to rei lieve rigidity in the finger action and permit a certain elasticity thereof. This is an important feature of my invention, as the link 115 being guided in its movements by the groove in the rocker, undue lateral play is prevented and extreme steadiness of finger action is obtained.

The fingers each comprises a base section 118 and a tip section 119,*the fingers being pivotally attached to the hand as by means of a finger pivot 120 extending laterally across the hand and through its side parts.

.A finger actuating lever 124 is pivotally attached at one end to each of the tip sections 119 of the fingers, the opposite end of each of said levers being attached to the finger actuating rod 135. Backward movement of the levers 124 from their positions beyond has a cam slot 126 formed-by a cam prong 127 extending from the back thereof. The bach edffe of each lever engages the pivots 120 and 125 and the back edge of each prong engages a base section operating pin 128 eX- tending across the slots in the fingers at the inneil end of each'base section thereof or the baclr rxdges of the levers may directly engage the bottoms of the slots in the base sections. The grooves S5 that receive the ends of the actuating rods 135 are inclined with respect to a plane passing centrally through the hand more or less parallel with the bacl; and front thereof, and as shown in Fig. 1 of the drawings.

This construction provides for aI peculiar movement of the fingers and one that is found especially desirable in enabling the hand to Ybe used for different purposes for which it is required. The `finger actuating rod 135 being moved by its actuating mechanism, each of the leversl2iis pulled to-.

ward the rear of the chamber 82. rlhe rod 135 traveling along the inclined slots causes the levers 124i to rock on the finger pivot 120 as a fulcrum carrying the outer ends of the levers forward and moving' the finger tips in this direction. This rocking movement of the levers also acts against the several pins 128 thus moving thepouter ends of the base sections of the fingers forward, carrying with them the tip sections, so that the tip sections have an accelerated movement caused by simultaneous pivotal movement of the base and tip sections. Y

rlhe finger actuating cord 90 passes over and under sheaves 13G-131 and through an opening' in the wrist to the outside thereof, as shown in Figs. 2 and 5 of the drawings, and along the forearm through proper guides to a point of attachment to ar vest (not shown) on the body of the wearer.

It will be noted from the above description that a pull upon the cord90 will move the lever 102, causing the pawl 105 thereon to move the ratchet one step, which, with the parts in the position shown` in Fig. 5 of the drawings, would move the holding teeth 96 from engagement with the holding dog 97. This action will permit the retaining slide 93 to move under the force of the spring 9S into position with the pawl 106 engaging the teeth of the rack 133. The lever 102 having been moved to engage the opposite end of its slot. with the pin 103 a continued pull upon the cord 90 will cause the carrier plate 91 to be swung on its pivot and it will be retained by the pawl 106 in any position to which it will be moved. This movement of said' plate exerts a pull upon the nger actuating levers 124i, imparting to them a closing movement as hereinbefore described, and in which position they will be held. This pull upon the cord 90 may be obtained by lowering the shoulder of the stump, to which the arm is attached, the latter being thus eX- tendedv awa)7 from the anchoring strap (not shown) to which it is secured.

lt will be noted that the thumb actuating' oord S0 is attached to the carrier plate on the opposite side of the pivot 99 from that at which the cord 90 is connected and nearer to said pivot so that the amount of thumb movement is less than that of the lingers.

The next succeeding pull upon the cord 90 will repeat the operation of the lever 102 and the pawl, but the dog 97 will be engaged with one of the holding teeth and the pawl 106 will be disengaged from its retaining rack. Upon force being now released from the cord 90 the main spring 136 will move the parts to their former position asshownl in Figf2 of the drawings, the lingers being thus opened and the lever 102 being returned to its former position under the action of the spring that operates upon the pawl 105. 1t will be understood that much of the hand will have a soft covering, as a form of glove, that may be of any desired color.

The forearm may be locked in different positions by means of a locking bar 35 pivotally attached to the upper armand extending into the lower arm, said locking bar having a longitudinal 'slot 36 with locking notches 37 at intervals along the edge 'of the slot to receive a locking pin 38 upon which a locking lever 39 is pivotally mounted, said pin being secured in a bridge 40 extending across the opening in the forearm and secured to the walls thereof. The end of the lever 39 projects through the forearm to the outer surface thereof where it may be manuallyoperated. rlhe lever 39 is in the form of a bell-crank lever one arm having lips ll1 projecting from the lever and lying upon opposite sides of the bar 35. From this description it will be seen that the lever 39 being swung on its pivot the bar 35 will be moved in one direction to disengage the pin 38v from one of the notches and the forearm being then bent to another position the pin will be engaged with another notch and the forearm may thus be locked in its new position.

ln order that the fingers may be freely closed and opened without being locked in either position, I provide a loclr release, in the mechanism herein shown this release comprising a lock releasing cam 42 secured to the inner end of a lock releasing shaft i3 mounted in the cover 34 and operating against the stud 101 to force the dog 97 from. engagement lwith the holding teeth 96,

positions, but it will be fcund that the curveV of the cam will be slight enough to obtain this result andl thereby answer all purposes.

The bar 35 may be retained in position 38 engaged with or disengaged with the pin by means of a spring 74 from thc notches as located on the pivot of the lever 39 and press! ing with one end against the inside of the forearm and with its opposite end against said bar, as illustratedV in Fig. 2 of the drawings. Y

In a prior application filed by me March 23rd, i917, of vSerial Number'157,032, an arm and hand mechanism is illustrated yand described embodying the following as a portion of its features:

A socket piece 46 secured manner in the opening` in the lower the forearm and having a recess opening into said arm, a hollow shaft 47 rotatably mounted in said socket piece and secured to the wrist piece 16, a coupling collar 48 slidably mounted on the hollow shaft and operated by a lever 49, said collar receiving a wrist turning cord 56, the operation of which to turn the wrist is described in my aforesaid application. A more ycomplete descripn tion of these parts is omitted herein as not necessary to the improvement as embodied in the present case and reference is hereby made to said copending application for such further information as may be desired with respect to said construction.

The present improvement embodies means for holding the hand in different positions with respect to the wrist piece 16, said hand 67 being mounted on a pivot 66 and having notches 68. The pivot 66 is mounted in projecting bearings 65 extending from the wrist piece, the latter having a circular shaped recess to receive the end of the hand, the latter being preferably formed on the arc of a circle.

A locking bolt 69 is located in the hollow shaft 47, said bolt being hollow and having a spring 70 located in the recess therein and thrusting `against a pin 7l projecting through said hollow sleeve. The end of the bolt hasa lug 72 that is forced by said spring into the notches 68, a hand locking lever 7 3 being engaged with the locking bolt as a means for operating it. This lever is pivotally mounted in the wrist piece 16 and pro jects out at the front thereof a short disin any desired end of tance and by its use the hand may be locked i means.

l. An artificial limb including a hand, fingers att-ached to the hand for bending movement, means for effecting bending movement of the fingers, mechanism movable independently of the bending means for locking the fingers in a bent position, and means operated always in one direction for effecting locking and unlocking movement, of said locking mechanism.

'2. An artificial limb including a hand, fingers attatched to the hand for bending movement, means for effecting said bendingrr movement, mechanism movable independently of the bending means for locking said means with the fingers in bent position and including a member movable in one direction to effect locking and unlocking movement thereof, and a cord attached to said member to operate it.

i). fingers attached to said hand for bending movement, means for bending the fingers, mechanism movable independently of the bending means for locking said fingers in bent posit-ion, and an actuator connected with the bending means and with the locking mechanism for operating both.

4. An artificial limb including a hand,

Vfingers attached to the hand for bendingA movement, means for bending the fingers, locking mechanism movable independently of the bending means for retainingthe fingers in bent position, said mechanism including a toothed member to receive and hold said locking member, and means for operating said locking member.

5. An artificial limb including a hand, fingers attached to said hand for bending movement, a rocking member connected with said fingers'to bend them, a lock movably mounted on said rocking member, mechanism for operating said lock and movable independently of the rocking member, and means for operating said lock actuating member.

6. An artificial limb including a hand, fingers attached to said hand for bending movement, a locking member to lock the fingers in bent position, a lock operating :iember having teeth to retain'the locking member in unlocked position, and an actuatmember operatively connected to move ing the fingers, to operate the lock actuating my invention, to-

An artificial limb including a. hand, .I

iisy

wheel rotatably mounted on the rocking member and having means to retain the locking member in one position, and an actuating member operatively connected with said toothed wheel and having movement independently of said rocking member.

8. A hand having lingers attached thereto for bending movement, a carrier plate operatively connected with the lingers, a retaining slide movably mounted on the plate, an jactuating lever pivotally mounted, connections between said lever and retaining slide to operate the latter and including means for holding the slide in one position, and means for connecting the actuating lever with the Vcarrier plate after the lever has e'ected part of its movement.'

9. A hand having lingersattached thereto for bendingmovement, a pivotally mounted carrier plate, a retaining slide movably mounted on the plate, a locking dog .to retain the slide inone position, a toothed wheel pivotally mounted on the plate and connected with said retaining slideto retain it in one position, and a ratchet and pawl connection between said lever ,and said toothed Wheel.

10. A hand having lingers attached thereto for bending movement, a carrier plate connected to bend said lingers, a retaining slide, an actuating lever operatively connectedl with` said slide, and movable independently of said carrier plate, and means lor connecting the lever with the carrier plate alter the lever has effected part of its movement.

11.V 'A hand having a linger attached thereto for bending movement, a movablymounted carrier plate operatively connected to bend said linger, a retaining slide movably mounted on said plate, a holding Adog pivotally mounted on said plate and operatively connected vwith the slide to operate it, and means lor operating said dog. l

12. A hand having a linger attached thereto for bending movement, a movably mounted carrier plate operatively connected to bend said linger, a retaining slide movably mounted on said plate, a dog pivotally supported on said plate, and slide operating mechanism including a toothed member arrangedto engage said., dog to operate it.

13. A hand having lingers, attached thereto lor bending movement, a movably mounted supporting bar,` a carrier plate movably mounted on said bar and operativelyjconnected to. bend said lingers, a retaining slide movably mounted onsaid plate, and means for operating said plate.

' 14. A hand having lingersattached thereto lor bending movement, a supporting bar having a limited yielding movement, a carrier plate movably mounted on saidbar and operatively connected to'bend said lingers, and means lor operating said plate.

15. A hand having a linger attached thereto for bending movement, a longitudinally movable linger actuating lever having a cam actuating surface, means lor moving said lever, and means on said linger adaptedto contact with said cam Vto ellect bending movement ol the linger by reason ol movement of said lever. 1

16. A hand having a linger attached thereto, said linger comprising, a base and a tip section, the base section being pivotally connected to the hand and the tipy section being pivotally connected to the basesection, an actuating lever pivotally connected with said tip section and having a cam" actuating surlace, meansfon the base section of the linger to contact with said Vc am to ell'ect bending movement ofsaid base section, andmeans for actuating the lever. f

l 1'?.V A'hand having a n'ger attached thereto, said linger comprising a base section pivotally attached to the hand and a tip section pivotally connected to the base section,l an actuatingA lever pivotally connected'with the tip section .andV also operatively connected to ubend the base section, and` means for operating said lever to effect bending movement ol.- the base section and simultaneous therewith andby reason thereof toV atleet an accelerated bending movement of the tipsection. Y

18'.V kA handhaving a linger attached thereto, said linger comprising a base section pivotally attached to the hand and a tip section pivotally connected to the base section, an actuatingl lever operatively connected with the tip section, means for moving said lever endwise to ellect bending movement of said tip'section, and means flor moving said lever laterally to ell'ect accelerated movement of said tip section,V Y

19. A handhaving lingers attached theretolorbending movement, a pivotally mounted carrier plate, a locking bolt slidably mounted on the plate, a toothed Wheel pivotally mounted on the plate to engage said locking bolt to retain it in one position, and

.a ratchet wheel and-pawl connection' between said lever and said toothed vvvheel.v 1 l 20. A .hand having a linger attached thereto, said linger comprising a base and a 'tipY section, an actuating lever comprising a ,cam lever, a connection between said lever and said base section of the linger for operating the latter, a `connection between said lever and saidA tip section for Voperating it, and means for operating the lever.

21. A hand having.VV a linger attached thereto, said linger comprising a base and nected to the base section, and means a tip section, an actuating lever pivotally connected with the tip section and having a cam surface, a guide to contact with said cam surface to effect lateral movement of the lever, and means for drawing said lever along said guide.

22. A hand, a thumb comprising a base section swivelly supported in the hand to turn on the aXis of said base section, and another section pivotally connected to the base section, andmeans for effecting bending movementof said pivoted section;

A hand, a thumb comprising a base section'swivelly supported in the hand to turn on the axis of said ybase section, means for locking the base section against swiveling movement, another section pivotally coneffecting bending movement of said pivoted section. Y

24. A hand having fingersy pivotally connected thereto, .a swinging bar, a connection .A between said bar onv one side of its pivot.

and :said fingers to effect bending movement of the latter, and a connection between said bar on the opposite side of said pivot and the thumb to effect bending movement of the latter. c

25. Al hand havingV fingersy attached thereto for bending movement, a finger actuating rod Voperatively connected with said fingers, a movably mountedy member operaf tively vconnected with said rod to operate it, means to support said movable member and prevent'tipping and consequent cramping action of said. rodand means for actuating said movably mounted member.

26. A hand `having fingers attached thereto for bending movement, a finger actuating rod operatively connected with said fingers, 4a sliding member connected with said rod to assist in its operation, and a guide for said sliding member to restrict sidewise swinging movement thereof.

27. A hand having fingers attached thereto for bending movement, a finger actuating rod operatively connected with said fingers, al movably mounted finger bending memberpivotally connected'with said rod, a link mounted on said pivot, means Ito connect the link-with said rod, and a guide for said link to restrict undue swinging movement thereof and thereby preventcramping actionof the finger actuating rod. Y i

2,8. A hand having fingers Y attached thereto for bending movement, a finger actuating rod operatively connectedwith said fingers, `a 'movably' mounted fingerV bending member pivotally connected with said ,rod at aplurality of points, and a link connecting said finger bending member and said rod,

said link being secured at said points.`

29. A hand havingv fingers attached thereto'for bending movement, a'finger actuating rod operatively connected iiithV said for guideway, andl means for pivotallyvconnecting said link to said finger bending member and with said rod. Y 1 f 30. A hand 'havingi fingers attached thereto for bending movement, a finger actuating rod operatively connetced Vwith said fingers, a :movably mounted finger bending member, ay rocker sup'portedin proximity to' said member and having a guideway, a link located in said guideway and pivotal-ly connected with said member and with said rod, and? a projection fromv said rod conf nected with said link at-one end yand with the pivot securingthe opposite end-of said link.'f4

31. A hand having fingers f attached thereto for bendingmovement', a fingeractuating rod operativelyconnected' Vwith 'said fingers, a movably mounted supporting bar, a finger bending member-movablymounted on saidfbarja'nd pivotally connected with said rod,ra guide attachedto said bar, and

member carried by vsaidv guide and .con-` f i necte'dto 'saidv fingerl bendingrv member YtoVV prevent cramping movement of said rod;.

32. A hand having fingers attaehedthere# to forbending movementya vfinger actuating rodk operatively connected 'with said fingers, a 'movably 'mounted supporting bar, a' rocker pivotally connected w'ithlsaid bar Vand having 'ai' guideway, a link mounted in said guideway, a finger bendingmem'ber opera" tively connected with said roch-and a pivotal connection between said fingerV bending member and said linkt',v

` 33 -A hand having fingers attached thereto for bendinglinovement, a'finger actuating rod operatively connected with said' fin` gers, a'pivotally mounted supportingy bar, afinger'bending member mountedion said bar,a rocker pivotally mounted on saidbar and having va'guideway, a link mounted in said guideway' and" connected with said finger bending member in proximity to the pivot of said rocker,"and la pivot'connecting the opposite end "of said' link with said rod, the vl'z'i-tter being connected with said member by means of the lastfmentioned pivot.

34; A hand having fingers attached there-4 to forbendin movement, a finger actuating f rod operative y connected with said fingers, a movably mounted finger bending member ice connected with said rod, a member for operating said finger bending member, a member forflocking said` finger bending member against movement, and mechanism for retaining said locking member in unlocked position to permit free opening and closing movement of the fingers.-` .Y

35,. A hand having fingers attached thereto for bending movement, a finger actuating rod operatively connected with said fingers, a movably mounted linger bending member pivotally connected with said rod, means for locking said member against movement, said means including a dog, and means for retaining said dog in position to prevent operation of the locking members and thereby permit free opening and closing movement of the lingers.

36. A hand having fingers attached thereto for bending movement, a finger actuating rod operatively connected with said fingers, a movably mounted finger bending member connected with said rod, means for locking said member against movement, said locking means including a dog, a cam mounted in the hand structure and operatively connected with said dog to hold it in position to prevent operation of the locking members and thereby permit free opening and closing movement of the fingers, and means for operating said dog.

37. An artificial limb including an upper arm and a forearm pivotally attached thereto, a locker bar pivotally connecting said members, said bar having a slot with locking notches, a stud to engage said notches to retain the bar in certain positions, and a lever in engagement with said bar to engage and disengage said notches with and from said stud.

38. An artificial limb including an upper arm and a forearm pivotally attached thereto, a support located in one of said arms, a locking bar pivotally attached to the other arm, said bar having a slot and locking notches in the edge thereof, a lever pivotally mounted on a stud extending from said support, and means engaging said lever with said bar to engage and disengage 'said notches from said stud.

39. An artificial limb including an upper arm and a forearm pivotally attached thereto, a bridge extending across one of said arms, a stud secured to said bridge, a lever pivotally mounted on said stud and having ylips projecting from one arm thereof, and

a locking bar pivotally attached to the other arm and having a slot with notches in the edge thereof, said bar resting between said li as.

140. An artificial limb including a forearm, a hand pivotally attached thereto on an axis extending transversely of the axis of the forearm, a locking bolt to positively retain the hand in different positions, means on the hand to receive said locking bolt, and means for operating said bolt.

4l. An articial limb including a forearm, a hand swivelly attached thereto and also pivotally connected therewith, a locking bolt located in line with the axis of said swivel to positively lock the hand against movement, and means on the hand, to receive said bolt to retain the hand in different positions.

42. An artificial limb including a forearm, a hand pivotally attached to the forearm, a hollow shaft swivelly connecting the hand with said forearm, a locking bolt mounted in said shaft, and means on the hand to receive said bolt to retain the hand in different positions.

43. An artificial limb including a forearm, a wrist piece, a hand'pivotally attached to said wrist piece with its edge extending inteV a socket therein and having locking notches in its edge, a hollow shaft swivelly attaching the wrist piece to the forearm, a locking bolt located in said shaft, and a bolt operating` lever extending through the wrist piece to the outside thereof.

dell. An artificial limb comprising members mevably mounted one with resoect to another, a loclring member for locking said members against movement, a lock actuator having a step-by-step movementto alternately place said lock actuator in locked and unlocked positions, and means for operating said lock actuator.

An artificial limb comprising members movably mounted one with respect to another, a locking member for locking said members againstV movement, a rotatably mounted lock actuator having a step-by-step movement to alternately place said lock actuator in locked and unlocked positions, and means for operating said locl actuator.

4G. n artificial limb comprising memcrs movably mounted one with respect to another, an operating member connected with one of said members and movable coexvtensive therewith, means .er locking said operating member against movement, lock actuator mounted for step-by-step movement to alternately place said lock actuator in locked and unlocked positions, and means for operating said lock actuator.

et?. A hand having fingers attached thereto for bending movement. carrier plate operatively connected with the fingers, a retaining` slide movably mounted on the plate, an aetuatinglever Apivotally mounted, connections between said lever and retaining slide to operate the latter and including means for holding the slide in one position, and means for Aoperatively connecting the actuating lever with the carrier plate to operate the latter.

48. A hand having fingers attached thereto for bending movement, a finger actuating rod operatively connected with said fingers,

a member movably mounted to aetuate said rod, a sliding member pivotally connected with said actuating member, and means for guiding said sliding member while permitting lateral play thereof.

OTTO LE GRAND DLTJNORTH, 

